docs: def write_config_file(self, parsed_namespace, output_file_paths, exit_after=False):
          """Write the given settings to output files.
  
          Args:
              parsed_namespace: namespace object created within parse_known_args()
              output_file_paths: any number of file paths to write the config to
              exit_after: whether to exit the program after writing the config files
          """
          for output_file_path in output_file_paths:
              # validate the output file path
              try:
                  with open(output_file_path, "w") as output_file:
                      pass
              except IOError as e:
                  raise ValueError("Couldn't open %s for writing: %s" % (
                      output_file_path, e))
          if output_file_paths:
              # generate the config file contents
              config_items = self.get_items_for_config_file_output(
                  self._source_to_settings, parsed_namespace)
              file_contents = self._config_file_parser.serialize(config_items)
              for output_file_path in output_file_paths:
                  with open(output_file_path, "w") as output_file:
                      output_file.write(file_contents)
              message = "Wrote config file to " + ", ".join(output_file_paths)
              if exit_after:
                  self.exit(0, message)
              else:
                  print(message)